I am not denouncing him as kafir.
The prophet said a man can become pious muslim all his life but one action before his death doom him to hell( meaning he is only pious on the outside but never sincere)
An evil person who does bad through his life but one noble action before his death brings him to hell( remember the hadith where a man who killed 99 people are allowed to enter heaven by allah mercy becuz his last action where he was travelling a long journey trying to ask people if he can still go to heaven after his evil deed meanjng he is very sincere in repenting))
As prophet also said, beware the danger does not lie from the outside(meaning the kafir) but the danger is from the inside( meaning the hypocrite, those who show their islamic identity on the outside, but on the inside he is the most evil person- meaning that he does islamic deed just for praise not sincere)
As prophet also said the the harm cause by the hypocrite outweigh the harm caused by kaafir because they can shatter the religious commitment of muslim.
This is exactly what this guy did to my relative. He grows beard, and does other deed, but he is evil on inside. He purposely taunt my relative in front of everyone, and theyre alone he remain quiet. His face is very unfriendlu